


One of us

by Coniferoussiblings



Category: Gravity Falls
Genre: Alternate Universe - College/University, Explicit Sexual Content, F/F, F/M, Friendship/Love, Multi, Pinescifica, Polyamory, Sibling Incest, Threesome - F/F/M, pinecest - Freeform
Language: English
Status: Completed
Published: 2015-11-15
Updated: 2015-11-15
Packaged: 2018-05-01 17:02:57
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,278
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5213822
Author URL: https://archiveofourown.org/users/Coniferoussiblings/pseuds/Coniferoussiblings
Summary: <blockquote class="userstuff">
              <p>Pacifica Northwest enjoys a dinner date with the Pines twins. College AU.</p>
            </blockquote>





	One of us

**Author's Note:**

> This fic is pretty much pwp. Pacifica and the twins are already in a polyamorous relationship with each other and this is just a glimpse at a nice night for them. No big dramatic moments or heavy plotlines, just some fluffy characterization and a dollop of smut.

There was something oddly satisfying about eating food that you had made yourself, Pacifica thought, even if she had technically only assisted Mabel with the cooking. Dipper had been banished from the kitchen and sent to pick up drinks from the corner store after his earlier attempt to get the meal started had set the fire alarm off and filled the small apartment with the acrid stench of burned rice.

Mabel had teased Dipper pretty mercilessly about the incident when he'd come back but Pacifica had decided not to join in the fun for once, unsure as she was of her own cooking skills. Even so she was pretty sure that she would have at least remembered to add enough water to the pot before putting the rice on the burner.

"Seriously Dipper, you're at the top of your chemistry class - how can you be so bad at this?" Mabel joked as she handed her brother a steaming plate of food.

"You've got me," Dipper said with a shrug, "I mean, logically it makes no sense. Maybe if I got to try cooking a meal over a Bunsen burner or attempted to make soup in a flask it would work out better?"

"So do you think it might be a psychological block then?" Pacifica suggested before popping another forkful of food into her mouth.

Mashed potatoes and gravy _a la_ Mabel might not be the same as the food cooked by the master chef's that her parents employed, but at this moment she couldn't remember the last time she'd tasted anything this good.

"Hmm, yes - we mustn't overlook the psychological possibility," Mabel said as she stroked an imaginary beard, and then continued in a terrible German accent, "We must get to the root of this problem - tell me about your mother Mr. Pines,"

"I'd think you'd already know enough about her considering that she's your mother too," Dipper shot back with a smile.

"Deflection, a classic technique of the paranoid mind." Pacifica opined in a perfectly deadpan voice, giving a quick yet professional nod toward Mabel.

A few tidbits of information from the psychology class she'd taken last semester were still floating around in her mind and a convenient one had just happened to spring up at the right moment to set Dipper's ears to flaming bright red.

"Hey, if any of us here is crazy it's obviously Madame Freud over there," Dipper said, a shade more defensively as he gestured toward Mabel with his loaded fork.

"Mr. Pines, you know we don't like to use the word 'crazy' in this office," Mabel teased back, still using her ridiculously over the top accent.

Dipper's stern expression managed to hold for about three seconds before he felt a smile split down his face. Mabel's complete lack of any kind of talent at accents and imitations had always been a weak point for him.

"Hah! I told you he still had a sense of humor - pay up!" Mabel said, turning to Pacifica and wiggling her fingers in a 'gimme gimme' gesture.

"Hey, what's that supposed to mean?" Dipper demanded of Mabel, his voice mild but with a slight edge to it.

"Face it Dip, ever since you started getting all super serious about graduation you've nurtured the stick up your butt into one of those giant redwoods that groups of old-timey lumberjacks used to take pictures next to," Mabel teased.

"I still have fun... I mean, just last week I put some sound effects in a computer presentation I had to do for my statistics class. Professor Bryers even smiled, and I was ninety-percent sure that he was just an anthropology lab mummy propped up in the teacher's desk for my first half of the semester," Dipper said.

He shifted uncomfortably in his seat as he felt the skeptical stares of Pacifica and Mabel turned toward him.

"Okay, so maybe I haven't been the life of the party lately," Dipper admitted with a sigh as he poked at the small steaming mound of mashed potatoes on his plate.

"Yeah, but all hope isn't lost for Captain Buzzkill yet... I think there may still be a chance to save you," Mabel said dramatically.

"I'm willing to try whatever therapy you've got in mind as long as the Fun-Stick isn't involved," Dipper replied.

"Skeptic. One day medical science will recognize the true potential of the Fun-Stick for treating these sorts of cases," Mabel said with a confident nod to herself.

"What's the Fun stick?" Pacifica asked, her eyebrows quirked as she glanced between her two hosts.

"Oh it was this surprisingly sharp branch that Mabel had found when we were kids that she used to jab in my face whenever she thought I needed cheering up," Dipper said flatly.

"Good times," Mabel recalled with a chuckle.

"For some of us," Dipper said.

"Ah," Pacifica said, "for a second there I... nevermind."

"Hmmm?" Mabel asked.

"It's really nothing," Pacifica said, feeling her cheeks flush slightly.

"I guess it's not," Mabel said lightly, "but all these attempts to distract me won't work - you still owe me for the bet,"

"Wait, you mean that there was an actual bet? I thought you guys had just been joking around." Dipper said.

"There may have been some actual talk of a bet at one point," Pacifica replied with an apologetic shrug.

The truth, of course, was that there was no such bet, but Pacifica had learned to play along with Mabel's improvisations when they came.

"I believe the terms were that I got a zillion dollars if I could get Mr. Serious over there to laugh without resorting to tickles," Mabel said.

Pacifica mimed patting the pockets of her jacket with a worried expression on her face.

"I seem to have left all my gold bricks and giant diamonds in my dorm, so I don't think I'll be able to cover it today," she joked.

Mabel's face split into a wide and surprisingly sinister grin and she steepled her fingers in front of her face.

"Oh I'm sure we can work out some other way that you can pay off your debt," Mabel said with a waggle of her eyebrows.

Pacifica felt the flush come back to her cheeks in full force at the look in Mabel's eyes... sure, she was kidding around but she could recognize a few not-so-subtle signs that this wasn't _all_ intended to be taken as a joke

Of course if that was the case Pacifica would be all too happy to oblige. In fact, she might even demand it if the rest of the evening went like she hoped it was going to.

After the trio finished dinner they headed over to the sparsely furnished living room of the twins apartment. There was a brief but lively debate about which movie they were going to watch until Mabel randomly shot a dart from an old Nyarf gun at the shelf full of movie discs and decreed that whatever she had hit would be their entertainment for the night. Neither Pacifica nor Dipper could find any objection to the idea and Pacifica started setting up the movie while the twins headed back to the kitchen to mix up some refreshments. Doctor Mabel had prescribed a heavy regimen of 'medicinal' drinking to cure Dipper's stick-in-the-mud condition, and he had agreed to put aside his studying for the night and enjoy the therapy session.

Mabel was the first to return from the kitchen and plopped herself down at the edge of the couch and patted the middle cushion of the seat for Pacifica to join her after she had finished messing with the twin's blu-ray player.

"What have you got there?" Pacifica asked when she saw Mabel holding a pink plastic cup decorated with a bunch of cartoon pigs in festive hats dancing along its sides.

"A Mabeltini – I just invented it a few minutes ago," Mabel said proudly, offering the drink up for inspection.

Pacifica glanced into the glass and her nose wrinkled at the overpowering smell of alcohol wafting out from the top. Candies floated on the surface of the drink, their bright dyes leeching into the liquid below to dye it a murky rainbow shade.

"Want a sip?" Mabel asked, waggling the glass at Pacifica in what she hoped was an enticing manner.

Politeness warred with self-preservation for a few seconds in Pacifica's mind before Dipper walked in from the kitchen with two mismatched glass tumblers in his hand.

"Here's that rum and Pitt you asked for," Dipper said, holding the glass toward Pacifica like someone throwing a life preserver out to a drowning victim.

Pacifica accepted the glass from Dipper's hand with a smile of thanks and shifted closer to Mabel on the couch so that he was able to join them. She gave an appreciative sigh after taking the first sip – cold, sweet and with just enough heat from the rum to give the drink a pleasant kick. Dipper may have been a failure as a chef, but if all his other career plans didn't pan out he would probably make a pretty decent bartender.

"Good?" he asked with a confident smile at the sight of her expression.

"Heavenly," she replied.

"I told you that chemistry class would pay off sometime," Dipper said to Mabel who was currently halfway through the drink of her own making.

"Bah, you guys just aren't able to appreciate the artistry of a well-made Mabeltini," she replied, swirling her plastic pig cup with a haughty toss of her hair.

"Just dumping a bunch of sprinkles and leftover Halloween candy into straight vodka isn't the same as actually mixing a drink," Dipper said.

"You said the same thing about the Cos-Mabel-itan, and the Mabel-on-the-Beach," Mabel said.

"That's because they are all the same drink Mabel," Dipper said.

"Let's just agree to disagree on that," Mabel said before taking an extra deep gulp of her colorful mixture and then coughing as the undiluted liquor hit the back of her throat.

"Are you okay?" Pacifica asked.

"Yeah. Good stuff," Mabel said, giving her a weak thumbs up in response while tears had begun to well up at the corners of her eyes.

"I'll just take your word for it," Pacifica said.

Once the trio had settled into the couch they started the movie and sat back in the darkness, sipping their drinks by the flickering light of the screen. The movie that Mabel had shot wouldn't have been any of their first, second or even third choices since it was a cheesy half-forgotten action film from the 80's that the twins had only bought because their Grunkle Stan had a bit part as an extra in the crowd during one of the chase scenes.

The movie was far from good, but the three kept up a light conversation and had snuggled in closer together on the couch after they had finished their first round of drinks and started working on their second. Pacifica was practically purring with contentment at the feel of Mabel's soft curves pressing up against her right side while Dipper's sturdy arm stretched out across her shoulders and his hand rested gently on the back of Mabel's neck.

Pacifica's own hands had been idly toying with one of Mabel's long curling strands of hair and she was contemplating leaning over to kiss a sprinkle left over from the Mabeltini off from the corner of her mouth when Mabel suddenly shot up and started pointing excitedly at the screen.

"Guys, I think Stan's cameo is coming up! I remember he said we'd be able to spot him because he was waving really hard at the camera," Mabel said.

"Wouldn't that have totally ruined the shot?" Pacifica asked.

"Yeah, but the production company was apparently out of money by that point and they couldn't afford to re-shoot the whole action scene so it stayed in. I think Stan said he got a lifetime ban from setting foot in Hollywood after that," Dipper replied.

"Your family has had a pretty colorful history haven't they?" Pacifica said in a dry voice as she took a deep sip from her drink.

"Hey don't be so snarky missy - you're practically part of the family yourself now," Mabel said in a teasing tone, poking Pacifica in a particularly ticklish part of her side.

"I don't know if I'd go that far," Pacifica said, her eyes dropping into the depths of her drink and a blush spreading across her face.

"Well you do come over to visit us quite a lot," Dipper said in a thoughtful tone of voice.

"Like, often enough that you have your own toothbrush and shampoo and stuff here," Mabel continued.

"In fact, I think you've probably slept over at our place more than your own apartment ever since you transferred over here," Dipper added.

"Possibly true," Pacifica said, feeling her face grow even hotter.

"I'd say that qualifies her as one of us, wouldn't you agree Lord Dippington?" Mabel asked.

"Yup, she's definitely one of us Lady Mabellina." Dipper agreed with a nod of his head.

"One of us," they said together.

At some unspoken signal the twins both turned to face Pacifica and began chanting the phrase at her in unison in ominous voices accompanied by spooky hand gestures until she felt the giggles start to well up out from deep inside her, leaving her breathless from slightly tipsy laughter.

"Alright, alright – you win. I'm one of you weirdos," she said after regaining some of her composure. The ice had nearly melted out in her drink and Pacifica downed the rest in a single long sip, enjoying the simultaneous feelings of cold and warmth that bloomed in her chest as she swallowed the last drop and felt it flow down her throat.

"That's not really a bad thing though is it?" Mabel asked in a coy voice, leaning in closer to Pacifica until she could practically feel Mabel's soft lips brushing up against hers.

"Not at all," Pacifica whispered, feeling the blood thrumming through her veins in anticipation.

"I thought so," Mabel said quietly before she caught Pacifica's lips in a kiss, filling her mouth with the faint taste of the candy staining Mabel's lips and tongue.

Pacifica tilted her head to deepen the kiss and moaned softly into Mabel's mouth when she felt Dipper's arms wind around her torso from behind and the not-unpleasant roughness of his stubbled chin brushing up against the crook of her neck as he bit down and sucked gently at her skin.

Pacifica's empty glass tumbled onto the carpet as one hand went out to wind her fingers into Mabel's hair and pull her closer into their increasingly frantic kiss. Her other arm groped out blindly behind her until she found her way to Dipper's thigh. Her fingers climbed their way up his leg until she heard him grunt in surprise and pleasure as she began to massage him through the thick cloth of his jeans. She gave a pleased hum into Mabel's mouth when she felt the effect her touches were having on him as he grew under her hand.

Her own hum became a gasp as his she felt his large hands slip underneath her shirt from behind, travelling up along her sides until he was cupping at her breasts through the lacy fabric of her bra. Dipper's lips broke contact with Pacifica's neck and he glanced up at Mabel.

"Little help here sis?" he asked.

Mabel's hands slipped up around Pacifica's back, deftly unhooking her bra, which Dipper pulled free before returning his attention to stroking and pinching the sensitive skin that had become exposed by the twins' teamwork. Mabel made a frustrated little noise in the back of her throat and broke the kiss, grabbing the hem of Pacifica's loose top and pulling it up over her head to leave her bare from the waist up.

Pacfica felt her face flush again hotly when she saw Mabel's hungry gaze travelling up her naked flesh, but she met her eyes with an equally hungry look of her own and thrust her chest out in an almost challenging manner. Mabel placed her small hand high up on Pacifica's breastbone, her palm still cold from holding her now discarded glass, and gently pushed her back until she was cradled up snugly against Dipper's torso. Pacifica turned her head back and caught Dipper's lips with her own in a wet kiss, sucking hard on his lower lip.

She had to resist the urge to bite down on it when she felt Mabel's own mouth latch onto her left nipple in a swirl of tongue and teeth that sent darts of pleasure shooting from her chest to the growing heat in the pit of her belly. Not wanting to be outdone, Dipper had moved his hands down along Pacifica's torso and pulled the material of her expensive skirt up around her waist. She felt her breath start to come in short gasps as he slipped a hand down the waistband of her underwear and his stroking fingertips zeroed in on her clit with practiced ease. Pacifica gave a loud moan and gnawed at her lower lip with her teeth as Dipper began to slide his digits against the small nub in the tight circles that he knew drove her absolutely wild.

It didn't take long. It never did when the both of them were on her like this, focusing their attention solely on heightening her pleasure. The combination of Mabel's eager mouth sucking and nipping at her chest and neck and Dipper's blunt but nimble fingers sliding wetly between her shaking thighs was just too much to take in, and she felt herself getting overwhelmed by the stimulation. Pacifica's back arched up off the couch as she felt herself drawing closer and closer to her orgasm, unconsciously grinding herself hard against Dipper's hand and babbling a frantic stream of alternating encouragements and curses while the sheer pressure of the pleasure flowing into her built up into something almost painful. All at once she felt the coiling tension inside her snap, and a high scream tore its way out from her throat as she came. Muscles that had been held rigid with anticipation went suddenly limp as Pacifica slumped back, deliciously drained, her breath coming in ragged pants while she lay herself against Dipper's chest as shifting colors danced behind her eyelids.

A small smile tugged up at the corners of Pacifica's lips as she felt Dipper slide his free hand into hers and his sister slipped her own hand into Pacifica's other empty palm, lacing their fingers together. Mabel bent down to brush a few strands of sweat slicked hair from Pacifica's face and then planted a tender kiss on her forehead, an affectionate ritual that Pacifica had come to love. Pacifica could practically feel the energy flowing up through the arms of the two and basked in the warmth of it. This was where she always felt like she most belonged, not surrounded by luxury but tucked away in the privacy she shared with the twins.

"I think tonight is off to a good start, don't you agree Dip?" Mabel asked her brother in a sing-song voice.

"Definitely," Dipper replied, and he leaned in and planted his lips against Mabel's, kissing her eagerly.

Pacifica watched the twins drawing into each other from below and felt the life flow back into her boneless limbs as she surged up to join them. She intended to fully repay the pleasure she had just received to the both of them before the night was through.


End file.
